A hybrid electronic control unit (70) of U.S. Patent Application Publication No. 2008/0018111 (hereinafter referred to as the “US 2008/0018111 A1”), sets a drive point of an engine (22) and torque commands Tm1* and Tm2* of motors MG1 and MG2 in a range between an input limit and an output limit of a battery (50), in order to satisfy a preset output power demand. Further, the hybrid electronic control unit (70) sends the drive point of the engine (22) to an engine ECU (24) and the torque commands Tm1* and Tm2* to a motor ECU (40), together with the input limit and the output limit of the battery (50) to the motor ECU (40) (Abstract).
The motor ECU (40) verifies whether the operations of the motors MG1 and MG2 with the torque commands Tm1* and Tm2* are in the range between the input limit and the output limit of the battery (50). When the operations of the motors MG1 and MG2 are out of the range between the input limit and the output limit of the battery (50), the motor ECU (40) resets the torque commands Tm2* and Tm2* to make the operations of the motors MG1 and MG2 in the range between the input limit and the output limit and controls the operations of the motors MG1 and MG2 with the reset torque commands Tm1* and Tm2*. This arrangement effectively prevents the battery from being overcharged with excessive electric power or from being over-discharged to supply excessive electric power even in the state of electric power imbalance due to a communication lag (Abstract).
The communication lag herein means a time delay by communication (paragraph [0003]). More specifically, the communication lag occurs in a period from the timing of making operation commands (torque command Tm1*, torque command Tm2*) to the timing of controlling the operations of power generation means (engine 22) or electric motors (motors MG1, MG2) ([0007]).